The invention relates generally to machines for laying composite tape on a mold or other part surface. In the field of manufacturing composite structures from successive plys of composite tape, a tape laying machine is utilized having a tape dispensing head which will lay down strips of tape in successive passes across a workpiece. The tape employed on tape laying machines, such as might be used in the aerospace industries, is generally manufactured from strands of reinforcement impregnated with a resin. The tape is carried on a paper backing strip coated with a release agent so that the tape may be impressed on a work surface at a tape laydown station. The paper leaving the tape laydown station is gathered on a take-up reel. Typical reinforcements may consist of graphite, Kevlar.RTM., boron, fiberglass, etc. and may be impregnated with epoxy resin, for example.
The tape comes to the machine user in predetermined reel sizes and nominal tape widths of three, six, and twelve inches, for example. The tape is manufactured at a width tolerance of from +0 to -0.030 inch from the nominal size.
The tape is fed from a tape dispensing reel on the machine and passes through a chute which guides the tape and provides a solid backing platen for the paper carrier strip as the composite tape is severed.
Manufacturers of composite tape structures require that the gap between side-by-side tape lay-down strips be maintained to a predetermined dimension. Some require butting of adjacent strips, while others require that a controlled gap width be maintained. Applicant has determined that due to the tolerance variation of the tape, a problem may be encountered when the tape is smaller than the chute width. The tape wanders to one side or the other, and a larger gap than is desired may result when laying tape bidirectionally. To overcome this problem, it would therefore be necessary to provide a different chute for each different width of tape within the tolerance.
For proper control of the tape, applicant has determined that the chute width must not be more than approximately 0.005 inch larger than the tape width or less than approximately 0.010 inch smaller than the tape width.
It is therefore an object of the present invention to provide an adjustable tape chute for use in a composite tape laying machine, in which the width of the chute guide portion may be varied to accomodate a given reel of tape.
Another object of the present invention is to provide for separately adjustable sides on a tape laying chute for use in a tape laying machine.
A further object of the present invention is to provide an adjustable tape chute for a tape laying machine in which the sides of the chute are independently adjustable and are calibrated to give a visual indication of an adjustment.